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Math Challenge II-A Number Theory

 
 
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Math Challenge II-A Number Theory
by Neo Liang - Wednesday, July 10, 2019, 8:25 AM
 

Lecture 6, Problem 6.20

Why isn't the answer -1?   -1=100 (mod 101)

 
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Re: Math Challenge II-A Number Theory
by David Reynoso - Wednesday, July 10, 2019, 11:59 AM
 

$-1$ is one of infinitely many correct answers. To have a unique answer we usually ask for a number between $0$ and $n-1$ ($n = 101$ in this case). Your answer was marked as correct on your quiz and the question was reworded to make it clear we want a number between $0$ and $100$ as an answer. Thanks for pointing this out!